Q: What are the objects and requirements of constitutional review in Japan, and what methods do courts use for constitutional adjudication (e.g., constitutional avoidance, as-applied vs. facial review)?

Judicial review of constitutionality is a vital safeguard in any system committed to the supremacy of its constitution. In Japan, Article 81 of the Constitution explicitly grants the Supreme Court (and by extension, all courts) the "power to determine the constitutionality of any law, order, regulation or official act." This power, however, is not exercised in a vacuum. Specific conditions must be met for a constitutional challenge to be heard, and courts employ a variety of methods in adjudicating such claims, often navigating a delicate balance between upholding constitutional norms and respecting the roles of the political branches. This article explores these crucial aspects: the objects subject to review, the prerequisites for review, and the judicial toolkit for constitutional adjudication in Japan.

Objects of Constitutional Review: What Can Be Challenged?

Article 81 provides a broad, illustrative list of what can be subject to constitutional scrutiny: "any law, order, regulation or official act." This is generally interpreted expansively.

1. Domestic Legal Norms and Their Application:
   • Laws (Hōritsu - 法律): Statutes enacted by the National Diet are primary objects of review.
   • Cabinet Orders and Other Executive Regulations (Meirei - 命令): This includes Cabinet Orders (seirei - 政令) issued by the Cabinet, as well as ministerial ordinances (shōrei - 省令) and other administrative rules.
   • Rules (Kisoku - 規則): This encompasses rules established by autonomous bodies within the state structure, such as the Rules of the Houses of the Diet (Article 58, paragraph 2) and the Rules of the Supreme Court (Article 77).
   • Local Ordinances (Jōrei - 条例): Legislative enactments by local public entities are also subject to review for consistency with the national Constitution.
   • Dispositions or Official Acts (Shobun - 処分): This category includes specific governmental actions that apply law to particular individuals or situations. It covers administrative dispositions (e.g., the issuance or denial of a license) and, according to prevailing case law and scholarly opinion, can also include court judgments themselves (as affirmed in early cases like the Code of Criminal Procedure Emergency Measures Act Case, Supreme Court, Grand Bench, July 7, 1948 [Shōwa 23]). Even fact-based governmental actions may fall under scrutiny if they raise constitutional issues.
2. Treaties (Jōyaku - 条約):
   Although Article 81 does not explicitly mention treaties, the dominant view in Japanese constitutional law is that treaties concluded by Japan are also subject to judicial review for their constitutionality. This view is supported by dicta from the Supreme Court in the Sunakawa Case (Grand Bench judgment, December 16, 1959 [Shōwa 34]). The rationale is that treaties, which often require only Diet approval (a simpler process than constitutional amendment), should not be allowed to override the supreme domestic law of the Constitution. A finding of unconstitutionality would primarily affect the treaty's domestic legal enforceability, though it would not automatically invalidate the treaty under international law; resolving the international obligation would then become a matter for the executive and legislative branches.
3. Legislative Inaction (Rippō Fusakui - 立法不作為):
   The failure of the National Diet to enact legislation that is constitutionally required can also be a subject of judicial review. This is particularly relevant where the absence of legislation leads to an infringement of fundamental constitutional rights.
   • Historically, challenging legislative inaction often took the form of damages claims under the State Redress Act, arguing that the Diet's failure constituted an illegal omission. However, courts set a very high bar for finding such inaction illegal, typically requiring the unconstitutionality of the inaction to be "clear and obvious" (e.g., At-home Voting System Abolition Case, Supreme Court, Grand Bench, November 21, 1985 [Shōwa 60]).
   • More recently, other avenues have been explored. The Supreme Court, in the landmark Overseas Japanese Voting Rights Case (Grand Bench judgment, September 14, 2005 [Heisei 17]), found that the Diet's failure to provide for overseas Japanese citizens to vote in national elections was unconstitutional. While a damages claim was also involved, the Court notably granted a declaratory judgment confirming the plaintiffs' eligibility to vote in future elections, demonstrating a more direct approach to remedying legislative inaction affecting fundamental rights.
4. Private Law Acts of the State (Kuni no Shihō-jō no Kōi - 国の私法上の行為):
   Whether actions taken by the state in its capacity as a private contracting party (e.g., buying or selling property) are directly subject to constitutional review for invalidation under Article 98(1) is debated. The Supreme Court in the Hyakuri Air Base Case (Grand Bench judgment, June 20, 1989 [Heisei 1]) held that such private law acts are not "other acts of government" in the sense of Article 98(1) that can be nullified for violating provisions like Article 9 (renunciation of war). However, most scholars critique this narrow interpretation, arguing that all state actions, regardless of their form, must ultimately conform to the Constitution.
5. Constitutional Amendments (Kenpō Kaisei - 憲法改正):
   The question of whether a formally adopted constitutional amendment can itself be subjected to judicial review for substantive unconstitutionality (i.e., for violating fundamental, unamendable principles) is a highly complex and largely theoretical debate in Japan, as no amendments have yet been made.

Requirements for Constitutional Review: Accessing the Judicial Forum

Because Japan operates an incidental (concrete) system of judicial review, several conditions must be met for a court to address a constitutional question:

1. Existence of a Concrete Case or Controversy (Justiciability):
   As mentioned, courts will only entertain constitutional issues that arise in the context of a genuine, specific legal dispute between identifiable parties. Abstract or hypothetical questions are generally not justiciable.
2. Standing to Raise Constitutional Claims (Iken Shuchō no Tekikaku - 違憲主張の適格):
   • Violation of One's Own Rights: Typically, a litigant must allege that the challenged law or governmental act infringes upon their own constitutional rights.
   • Third-Party Standing: While generally restrictive, Japanese courts have, in certain exceptional circumstances, allowed a litigant to assert the constitutional rights of a third party not before the court. The seminal case is the Third-Party Property Confiscation Case (Supreme Court, Grand Bench, November 28, 1962 [Shōwa 37]), where a criminal defendant was permitted to challenge the constitutionality of a procedure for confiscating property owned by a third party who was not given notice or an opportunity to be heard. The Court considered factors like the defendant's own interest (the confiscation was an additional penalty for him) and the difficulty the third party would face in asserting their own rights. Scholarly debate continues on the precise scope and criteria for allowing third-party standing.
   • Overbreadth and Vagueness: Particularly in cases involving freedom of expression, a party whose conduct might be legitimately proscribed by a narrowly drawn statute may still be permitted to challenge the statute as unconstitutionally vague or overbroad, arguing that its imprecision or excessive scope could "chill" the legitimate exercise of constitutional rights by others. The Supreme Court has entertained such claims, for example, in the Hiroshima City Bōsōzoku (Hot-Rodder Gang) Expulsion Ordinance Case (Third Petty Bench judgment, September 18, 2007 [Heisei 19]).
3. Ripeness and Mootness (Continuity of Interest in the Suit - Uttae no Rieki no Keizokusei):
   The constitutional issue must be "ripe" for decision, meaning it's not premature or speculative. Conversely, it must not have become "moot," where the underlying dispute has been resolved or circumstances have changed such that a court ruling would have no practical effect. However, the Supreme Court has occasionally addressed important constitutional questions even in cases that had become technically moot, if the issue was of significant public interest and capable of repetition yet evading review (e.g., the May Day Plaza Use Permit Case, Grand Bench judgment, December 23, 1953 [Shōwa 28]; and the Asahi Litigation concerning welfare benefits, Grand Bench judgment, May 24, 1967 [Shōwa 42], where the Court addressed the merits "for good measure" despite the plaintiff's death).

Judicial Methods in Constitutional Adjudication

When confronted with a constitutional challenge, Japanese courts employ a range of interpretive techniques and adjudicatory methods:

1. Facial Review vs. As-Applied Review (Bunmen Shinsa to Tekiyō Shinsa - 文面審査と適用審査):
   • Facial Review: Involves examining the text and inherent features of a law or regulation to determine if it is unconstitutional on its face, irrespective of its specific application in the pending case. A finding of facial unconstitutionality (hōrei iken - 法令違憲) implies the law itself is flawed.
   • As-Applied Review: Focuses on whether the law, even if potentially constitutional on its face, is unconstitutional in its specific application to the facts of the particular case before the court. This can lead to a finding of as-applied unconstitutionality (tekiō iken - 適用違憲).
     While Japanese courts and scholarship have historically engaged more readily with facial challenges (perhaps contributing to judicial restraint due to the broader implications of such rulings), there is a growing academic emphasis on prioritizing as-applied review as a means to make constitutional adjudication more context-sensitive and potentially more "active."
2. Review of Legislative Facts (Rippō Jijitsu no Shinsa - 立法事実の審査):
   Courts are not limited to examining only the "adjudicative facts" (facts specific to the case). They may also consider "legislative facts"—the broader social, economic, or scientific data and assumptions that informed the legislature's decision to enact the challenged law. This allows courts to assess the rationality, necessity, and proportionality of the law in achieving its stated objectives. A prominent example is the Pharmaceutical Affairs Law Case (Supreme Court, Grand Bench, April 30, 1975 [Shōwa 50]), where the Court scrutinized the factual basis for restrictions on the establishment of new pharmacies.
3. Doctrine of Constitutional Avoidance (Kenpō Handan no Kaihi - 憲法判断の回避):
   A strong prudential principle in judicial review is that courts should avoid ruling on constitutional questions if a case can be resolved on other grounds (e.g., statutory interpretation, procedural issues). This reflects judicial self-restraint and deference to the legislative branch.
4. Methods of Adjudging Constitutionality (Gōken Handan no Hōhō - 合憲判断の方法):
   When a law is challenged but ultimately upheld, courts may use several approaches:
   • Outright Declaration of Constitutionality (Gōken Hanketsu - 合憲判決): A direct ruling that the law or act is constitutional.
   • Constitutionally Conforming Interpretation (Kenpō Tekigōteki Kaishaku - 憲法適合的解釈): If a statute is ambiguous and open to multiple interpretations, one of which would render it unconstitutional and another constitutional, courts will, where possible, adopt the interpretation that upholds its constitutionality. This respects legislative intent while ensuring constitutional compliance. The Zentei Tokyo Central Post Office Case (Supreme Court, Grand Bench, October 26, 1966 [Shōwa 41]), concerning restrictions on public sector workers' labor rights, is often cited as an example.
   • Narrowing Construction / Severance (合憲限定解釈 - Gōken Gentei Kaishaku): If a statute is drafted broadly and could potentially be applied unconstitutionally in some contexts, a court might interpret it narrowly to cover only its constitutionally permissible applications, or, if the unconstitutional portion is textually severable, strike down only that part while upholding the remainder. The Customs Inspection Case (Supreme Court, Grand Bench, December 12, 1984 [Shōwa 59]), which interpreted the term "injurious to public morals" in customs law restrictively to mean "obscene" for the purpose of import prohibitions, is a key example. However, this technique has limits; it should not amount to a judicial rewriting of the statute contrary to clear legislative intent, a point highlighted by the Supreme Court in the Zennōrin Keishoku-hō Case (Grand Bench judgment, April 25, 1973 [Shōwa 48]).
5. Methods of Adjudging Unconstitutionality (Iken Handan no Hōhō - 違憲判断の方法):
   If a law or act is found to violate the Constitution:
   • Facial Unconstitutionality (Hōrei Iken):
     • Total Unconstitutionality (Zenbu Iken - 全部違憲): The entire law or a specific statutory provision is declared unconstitutional and void. Early landmark unconstitutionality rulings by the Supreme Court, such as the Patricide Provision Case (Grand Bench judgment, April 4, 1973 [Shōwa 48]) and the Pharmaceutical Affairs Law Case, took this form.
     • Partial Unconstitutionality (Ichibu Iken - 一部違憲): Only a specific, severable part of a law or provision is found unconstitutional. This can be a particular phrase, clause, or even a specific meaning or application that can be carved out while leaving the rest intact. Recent Supreme Court decisions have increasingly utilized this more nuanced approach, for example, in the Overseas Japanese Voting Rights Case (invalidating a part of the Public Offices Election Act that restricted voting rights) and the Re-marriage Prohibition Period for Women Case (Grand Bench judgment, December 16, 2015 [Heisei 27]) (finding the 6-month period unconstitutional only insofar as it exceeded 100 days). The Nationality Law Case (Grand Bench judgment, June 4, 2008 [Heisei 20]), which found an "excessive requirement" in the law to be unconstitutional, also points in this direction.
   • As-Applied Unconstitutionality (Tekiyō Iken - 適用違憲, in its narrow, specific sense): The law itself may be generally constitutional, but its particular application to the specific factual circumstances of the case before the court is found to violate a constitutional right. While the Supreme Court has not explicitly adopted this terminology for its own final rulings often, lower courts have sometimes made such findings.
   • Unconstitutionality of a Specific Disposition (Shobun Iken - 処分違憲): Here, the underlying law may be deemed constitutional, but the specific governmental action or administrative disposition taken pursuant to that law is found to be unconstitutional. The Ehime Prefecture Tamagushi-ryō (Shinto offering) Case (Supreme Court, Grand Bench, April 2, 1997 [Heisei 9]) found a specific instance of public expenditure for Shinto rituals by a local government to be an unconstitutional violation of the separation of religion and state, without invalidating the general laws governing local government finance.

Conclusion: A Multifaceted Approach to Constitutional Adjudication

The system of judicial review in Japan provides a comprehensive, albeit cautiously exercised, mechanism for scrutinizing governmental acts against the supreme law of the Constitution. The scope of reviewable objects is broad, encompassing most forms of state action and even legislative inaction, although access to this review is conditioned by requirements of standing and justiciability inherent in an incidental review system. In adjudicating constitutional claims, Japanese courts employ a diverse toolkit of interpretive methods, ranging from doctrines of avoidance and constitutionally conforming interpretations to, when necessary, outright declarations of unconstitutionality. These methods reflect the judiciary's complex role in upholding constitutional supremacy while navigating its relationship with the political branches of government and ensuring the continued functionality of the legal order.